Because the pressure is a key feature of the internal ballistic inside

change curve of the pressure with time can show the circumstance of internal ballistic inside.Increasing the pressure measurement accuracy

it can promote the research of the internal ballistic theories.There is an electromagnetic environment when the electro-thermal chemical gun（ETCG） is launched.The electromagnetic interference（EMI）brought some problems to measure the ETCG bore pressure.So the electromagnetism shield and the digital fiber-optic transmission technique are adopted

which resolved the difficult question goodly.At the same time

it can display the voltage and current of the plasma load

the ETCG bore pressure

ETCG muzzle pressure

and the signal of the ETCG muzzle speed in unifying on the same time stalk.It finds out the viable experiment method to research the theories of ETCG plasma electricity fire and electricity enhance function.